Inhomogeneous chemical evolution and galactic stellar populations

Metallicity distribution functions (MDFs) are an essential probe of galactic chemical evolution and star formation history, as illustrated for example, by the classical G-Dwarf Problem. I present a rudimentary, closed-box model for inhomogeneous chemical evolution in the limit of no mixing, and incorporating a contamination filling factor Q. In contrast to homogeneous models, this approach allows fitting the high-metallicity tail of the Galactic disk MDF. There is also excellent agreement with the Galactic halo and bulge metallicities. The results offer a revised interpretation of the observed MDFs and details of gas infall implied by the G-dwarf Problem.